Let-off motion for looms



LET-OFF MOTION FOR LOOKS Filed Oct.' 7, 1.922

gwuewkoz Patented rrics.

LmTNARD L. HAWKINS, OF GREENVILLE, SOUTH CAROLINA, ASSIGNOR OF ONE-HALF T0 CHARLES T. HUGHES, OE GREENVILLE, SOUTH CAROLINA.

LET-OFF MOTION FOR LOOMS.

Application led October '7, 1922. Serial.` No. 592,984.

To all whom t may concer/n Be it known that I, LENNARD L. HAW- KlNs, a citizen of the United States, residing at Greenville, in the county of Greenville and State of South Carolina, have invented certain new and useful Improvements in Let-Off Motions for Looms, of which the following is a specification, reference being had to the accompanying drawings.

The purpose of the present invention is to provide a device of this kind for governing the speed with which the yarn lets o from the top or secondary beam or roller to the whip roller.

Another purpose isto provide a let-off particularly adapted for use in connection with all constructions of looms, whereas others can only be used on looms involving particular constructions, and cannot, without difficulty, be used on Draper looms.

A further purpose is to provide an improved let-of motion, whichis simple, etlicient-and practical, not only due to its being capable of use on all'constructions of looms, but also due to the fact that it may be manufactured for a relatively low cost.

A still further purpose is the provision of a let-olf also comprising a friction band brake, for the top or secondary beam or roller, in combination with means to be actuated by the tension on the whip roller of the loom, to lessen the action of the friction band brake against tensioning means, there'- by permitting the yarn to freely let off from the top or secondary beam or roller to the whip roller. As soon as the tension on the whip roller decreases, the tensioning means of the friction band brake increases the friction of the band, and thereby lessening the speed with which the yarn lets of from the top or secondary beam or roller. These operations automatically occur, so that the speed with which the yarn lets off from the top or secondary beam is governed with accuracy.

It is to be understood that-the particulars herein given are illustrative and that while still keeping within the scope of the invention, any desired modifications of detail and desired proportions may be made in the apparatus according to circumstances.

The invention comprises further features and combination of p arts, as will be hereinafter set forth, shown in the drawings and claimed. f Y l In the drawings i Figure 1 is a view in vperspective ofthe improved let-od motion as applied to a portion of a loom; Y l

Figure 2 is a vertical section showing the parts in different positions, due to the fact that the friction of the band brake has been lessened on the top or Asecondary beam or .roller Figure 3 is an enlarged detail view of the stand 21. v l Y l Y Referring to the drawings, l designat the frame of the machine, and 2 designates the top or secondary beam or roller of the loom, from whichthe yarn lets off during the operation of theloom.- This top or sec,-

4ondary beam. or roller 2 has Va vpulley 3 at one end, it being .obvious that the lpintles or shafts of the top orsecondary beamor roller are mounted in bearings of the frame of the loom. A friction band brake" 4 engages about the pulley 3 Vbetween its annular flanges, and one end of this friction brake band has a reinforced loop 5,*which is connected to a bolt 6, which in turn. engages through a slot 7 in an upright 8 of the frame of the loom. This bolt is capable of adjustment in the slot, and by means of the nuts 9, the bolt may be held in different positions.

The reinforced loop end of the friction brake band is slotted as shown, and pivotally mounted upon the bolt 6 is a lever 10. This lever engages` the slottedportion of the reinforced loop ofthe friction brake band, so as tohold the lever centrally disposed with respect to the brake band. The lower edge of the lever Vis providedwith V-shaped notches 11. a'Ihe other end ofthe friction or link 13 is connected yto a transverse pin 14 which engages the reinforced loopof the friction brake b'and, and the lower end of the stirrup or link has a slot 15 through which the lever 10 engages, whereby the lower end of the slot 15 may engage in one of the notches 1l.

An arm 16 is fastened at 17 to a rearwardly inclined portion 18 of the frame, and connected to the lower end of this arm in a notch thereof is a tension coil spring 19, which in turn is connected to the extremity of the lever 10 as at 20. Obviously the spring 19 tensions the lever 10, and thereby holds any one of the notches 11 in engagement with the lower end of the slot 15 of the stirrup or link 13. This construction and arrangement of the aforesaid parts enables the tension upon the frictionv brake band to be increased or decreased, according to the desired speed with which the yarn is to be let o from the top or secondary beam or roller. Y

A stand 21 is mounted at 22 and is provided with a slot 23. The end portion of this stand has a laterally extending U- shaped extension 24, which is slotted in its under portion as shown at 25. A suitable whip roller 26 is mounted in suitable bearings in the ends ofthe stand 21, and over this roller passes the yarn V2'?" being let 0E from the top or secondary beam or roller 2. Obviously in letting off the yarn, it tensions on the whip roller 26, and it is the aim of the present invention to govern the speed with which the yarn lets off from the top or secondary beam or roller.

A secondary stand 28 is mounted upon a bolt 29, which is adjustably engaged within the slot 23 of the main stand 21.

An equalizing lever 30 is pivotally mounted upon the bolt 31 which is carried by the secondary stand 28, and the upper end of the equalizing lever has a lateral arm 32, which engages under the lever 10. The lower end of the equalizing lever 30 engages in the slot 25 ofthe lateral U-shaped portion of the stand 21.

Obviously when the yarn in passing from the top or secondary beam or roller tightens, or the tension increases, in passing. about the whip roller andv then to the drop wire heddle eyes 33, the friction brake band tightens frictionally upon 'the let-olf pulley 3. When this tension increases sufficiently, the whip roller 26 bears uponthe lower arm of the equalizing lever 30, causing a pivotal action of the equalizing lever 30, such as will cause the arm 32 to press under the lever 10, raising the lever 10 against the action of the spring 19, and thereby relieving the increased tension or friction on the friction brake band, in which case the yarn will let-olf more freely from the topvor sec? ondary beam or roller. As soon as this tension of the yarn decreases inpassingy from the'whip rol-ler to the heddle eyes, the pressure of the whip roller on the lower arm of This frictionlet-oif holds the yarn to the degree of tightness desired. As the yarn tightens in passing over the whip roller 26 it causes downward pressure uponk the forward or lower end of the equalizing lever 30, whereupon the upper end thereof exerts upward pressure against the arm 10 against the resistance of the spring 19 and this results in reducing thev friction of the band Il upon the pulley 3. 'This equalizing lever is, as previously stated, rsupported upon the stand 21, by means of a secondary stand 28. As the pressure from the whip roller 26 is transmitted to the equalizing lever 30, which is pivoted at the center, it causes the upper end to raise the lever 10, thereby slackening the stirrup or link 13, whichv is at'- tached to the friction brake band Ll.

Y The invention having been set forth, what is claimed is 1. A let-oft' for looms, the combination with the yarn roller and whip roller,.of a pulley on one end of the yarn rollera brake band engaged about the pulley and having one end anchored, a pivoted lever connected with the other end of the band, a tensioned spring applying pressure to said lever for eis causing the band to grip the pulley, a stand mounted on the frame of the loom and supporting the whip roller, the stand being formed with a slot, an arm pivoted on the stand and having its upper end engaging against the underside of said lever and having its other end extending through said slot and engaging the whip roller.

V2. A yarn let-o regulator for looms, the loom including a frame, a yarn roller and a whip roller; comprising a pulley on the yarn roller, a lever pivotally and adjustably mounted on the frame, a friction bandencircling said pulley and having one'end secured to said pivot and its other end adjustably engaged upon the lever, avspring connected with said lever and the frame for applying tension to the band, a stand mounted on the frame and provided with bearings for the whip roller, said stand being slotted,

a support adjustably mounted upon the stand, and a Vdouble ended arm pivoted on said support and having one arm engaging beneath the lever and it-s other arm extend'- ing through said slotand engaging the ui1- derside of the whi roller.

3. In a loom inc uding a yarn roller and a whip roller, a friction band engaged upon its lower side, and a pivoted arm having 10 one end of the yarn roller, a spring pressed its upper end engaging said lever and its lever connected with one end of the band lower end extending through said slot and for applying tension thereto, a stand carengaging the whip roller.

5 ried by the frame of the loom and having In testimony whereof I hereunto aix my 'bearings for slidably and rotatably supportsignature. ing the whip roller, the bearings being formed with a slot extending upwardly from LENNARD L. HAWKINS. 

